CVE-2023-41895
📋 TL;DR
This Cross-site Scripting (XSS) vulnerability in Home Assistant allows attackers to execute arbitrary JavaScript on the administration page by exploiting improper validation of redirect URIs. Attackers can use this to fully compromise Home Assistant accounts and installations. All Home Assistant users with versions before 2023.9.0 are affected.
💻 Affected Systems
- Home Assistant Core
📦 What is this software?
Home Assistant by Home Assistant
⚠️ Risk & Real-World Impact
Worst Case
Full account takeover leading to complete control of the Home Assistant installation, potentially enabling further attacks on connected smart home devices and systems.
Likely Case
Session hijacking, credential theft, and unauthorized access to home automation controls.
If Mitigated
Limited impact with proper network segmentation and strong authentication controls, though XSS could still expose sensitive data.
🎯 Exploit Status
Requires user interaction (clicking malicious link) but exploitation is straightforward once the malicious page is crafted.
🛠️ Fix & Mitigation
✅ Official Fix
Patch Version: 2023.9.0 and later
Vendor Advisory: https://github.com/home-assistant/core/security/advisories/GHSA-jvxq-x42r-f7mv
Restart Required: Yes
Instructions:
1. Backup your Home Assistant configuration. 2. Update Home Assistant to version 2023.9.0 or later via the Supervisor panel or command line. 3. Restart Home Assistant to apply the update.
🔧 Temporary Workarounds
No workarounds available
allThe vendor advisory states there are no known workarounds for this vulnerability.
🧯 If You Can't Patch
- Restrict network access to Home Assistant web interface using firewall rules to only trusted IP addresses.
- Implement strong authentication controls and monitor for suspicious login attempts.
🔍 How to Verify
Check if Vulnerable:
Check your Home Assistant version in the Configuration > Info panel or run 'ha core info' in the terminal.Check Version:
ha core info | grep 'version'Verify Fix Applied:
Confirm version is 2023.9.0 or higher in the Configuration > Info panel.📡 Detection & Monitoring
Log Indicators:
- Unusual authentication attempts
- Suspicious redirect patterns in web logs
Network Indicators:
- HTTP requests containing javascript: scheme in redirect parameters
SIEM Query:
web_requests WHERE url CONTAINS 'javascript:' AND destination_ip = [HOME_ASSISTANT_IP]